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The one-pot Prins–Friedel–Crafts reaction of aldehydes, a homoallylic alcohol and aromatics catalyzed by large-pore zeolites is an attractive environmentally friendly route towards valuable heterocyclic compounds containing a 4-aryltetrahydropyran moiety.

Although irrefutable evidence for the presence of signs of diamondiferous kimberlite on the Taimyr Peninsula were obtained in the 1930s, it was only in 2020 that a macrodiamond (>1 mm) was first discovered in Eastern Taimyr. This was a colorless laminar crystal of a transitional shape from an octahedron to a rhombododecahedron. According to the set of features, the crystal is rare and atypical of the known primary and alluvial deposits of the Siberian Diamond Province. The find of this diamond indicates the presence of primary sources and the need for medium-scale geological survey and exploration over a large area from Anabar Bay (Pronchishchev Ridge) to the west to the Kiryaka–Tas and Tulai–Kiryaka highlands and to the northeast to Tsvetkov Cape.

The paper reports on the deep geophysical studies performed by the Geological Survey of Russia (VSEGEI) under the international project – Deep Processes and Metallogeny of Northern, Central and Eastern Asia. A model of the deep crustal structure is represented by a set of crustal thickness maps and a 5400-km long geotransect across the major tectonic areas of Northeastern Eurasia. An area of 50000000 km2 is digitally mapped in the uniform projection. The maps show the Moho depths, thicknesses of the main crustal units (i.e. the sedimentary cover and the consolidated crust), anomalous gravity and magnetic fields (in a schematic zoning map of the study area), and types of the crust. The geotransect gives the vertical section of the crust and upper mantle at the passive margin of the Eurasian continent (including submarine uplifts and shelf areas of the Arctic Ocean) and the active eastern continental margin, as well as an area of the Pacific plate.

The paper is dedicated to the overview of the autonomous ship onboard control system functionality. The paper is dedicated to autonomous maritime navigation, i.e. to planning a safe and optimal route for an autonomous ship amid the absence of crew on board and to handling an autonomous ship when underway, ensuring seaworthiness and route correctness. Moreover, the paper describes communications of several autonomous ships and autonomous and ordinary ships to infer a collective decision on how to pass safely through a particular area. Since it is expected that autonomous ships are going to be equipped with dozens of sensors and detectors, the paper describes remote monitoring of an autonomous ship when underway. Since an autonomous ship highly depends on its onboard control system, the paper also pays attention to the robustness of the system. The paper suggests evolutionary computations as a solution for the route planning problem because this approach enables to perform multicriteria optimization of a set of solutions simultaneously. For autonomous ship handling and seaworthiness control, the paper suggests machine learning techniques because these techniques can solve problems in case of uncertainty and the environmental mutability. For inter-ship communications, the paper suggests distributed consensus algorithms, widely used in parallel and distributed computation systems. To ensure the onboard control system robustness, the paper suggests the actor approach that represents that the entire software system consists of a set of elementary agents communicating in the distributed computational environment.

This paper is dedicated to an overview of components of an onboard control system of an autonomous ship. This system controls and operates the ship. Therefore, this system needs to be able to analyze the ship’s state, predict its future development and analyze the consequences of its own decisions. The paper focuses on software aspects of the onboard control system, not the hardware. The paper provides an overview of technologies that can be used to implement the components of such a system responsible for planning new routes, handling the ship during the voyage, ensuring its seaworthiness and safety during the voyage, monitoring an autonomous ship from an onshore control centre, ensuring the robustness of the onboard control system, and collective operations of multiple autonomous ships. The paper describes benefits the maritime industry would gain from deploying some of the technologies developed for autonomous ships on ordinary, human-controlled ships. The paper also describes some challenges, especially in the field of automatic decision and reasoning, arising from the emergence of autonomous and smart ships. The main contribution of the paper is that it summarizes existing research in different areas of autonomous ship technology.

The locomotion of droplets in emulsions is of practical significance for fields related to medicine and chemical engineering, which can be done with a magnetic field to move droplets containing magnetic materials. Here, we demonstrate a new method of droplet locomotion in the oil-in-water emulsion with the help of a nonuniform magnetic field in the case where magnetic nanoparticles (MNPs) are dispersed in the continuous phase of the emulsion. The paper analyses the motion of the droplets in a liquid film and in a capillary for various diameters of droplets, their number density, and viscosity of the continuous phase of the emulsion. It is established that the mechanism of droplet locomotion in the emulsion largely depends on the wettability of MNPs. Hydrophobic nanoparticles are adsorbed on the droplet surfaces, forming the agglomerates of MNPs with the droplets. Such agglomerates move at much higher velocities than passive droplets. Hydrophilic nanoparticles are not adsorbed at the surfaces of the droplets but form mobile magnetic clusters dispersed in the continuous phase of the emulsion. Mobile magnetic clusters set the surrounding liquid and droplets in motion. The results obtained in this paper can be used in drug delivery.

Over a period of the past 15–20 years, the Russian Government implemented the Arctic Mega Project for geological and comprehensive study of the Arctic Ocean. In this paper we discuss the methods that were used in the implementation of this project. In the course of several expeditions, multiple types of data were acquired, which included: (1) seismic data of different types, (2) subbottom profiler data, (3) geological sampling on slopes of the Mendeleev Rise with the use of special equipment, (4) borehole drilling, (5) gravity and magnetic anomalies, (6) offshore geodetic data, (7) multi-beam bathymetry surveys, and (8) field surveys on multiple Arctic islands. Several nuclear icebreakers and a scientific research submarine were deployed in these operations. Specifically, more than 23,000 km of 2D multi-channel seismic lines and more than 4000 km of wide-angle refraction/reflection seismic lines were acquired, in addition to subbottom profiles for the Eurasia Basin and new bathymetric data of the Arctic Ocean. The new database is intended to facilitate the development of new insights into Arctic geology and geodynamics and contribute to a better understanding of the structure and tectonic evolution of the Arctic Ocean as a whole.

The paper presents a method to validate and refine the ship’s route during the voyage. The method consists in computing several characteristic coefficients that represent different aspects of the route, every time the ship arrives at a route’s waypoint. When the ship moves in a way that was not prescribed by the route, the coefficients deviate from those computed for the prescribed route. It is therefore possible to determine whether the actual route of the ship satisfies safety and optimality requirements. The coefficients may also change as a result of external impact or event. In case of such events, it is important to determine whether these changes affect the route’s safety and optimality. Therefore, the process of route temporal development can be expressed through changes of the coefficients and it is possible to predict future route changes based on the history of changes of the coefficients. The paper describes the proposed characteristic coefficients, the process of route refinement and the method for prediction and validation of the route’s future changes.

Special Issue: Abstracts of the International Symposium on Deep Earth Exploration and Practices, 1–5 Nov 2021, Nanjing, China

Expeditions carried out in the Arctic in recent years resulted in the accumulation of a significant amount of new information, which allowed better understanding the geology of the islands and coastal areas of the Arctic Ocean. Overviews on geology and evolution for the Severnaya Zemlya archipelago, the Taimyr Peninsula, the New Siberian Islands, the Wrangel Island and the areas of the Verkhoyansk Fold-thrust Belt adjacent to the Arctic Ocean, the Kolyma-Omolon Superterrane and the Chukchi-New Siberian Fold Belt include tectonic-stratigraphic maps showing petrographic composition, paleogeographic and lithogeodynamic conditions for the formation of sedimentary complexes, the phasing of tectonic and magmatic events.

The deep model of the Earth’s crust and upper mantle of the Arctic basin is represented by a series of velocity sections along the DSS profiles and a set of maps showing the thickness of the sedimentary cover, the thickness of the Earth’s crust as a whole and the distribution of the continental and oceanic types of the Earth’s crust in the Circumpolar Arctic. Crustal Thickness Map is based on results of deep seismic studies and gravity field anomalies in the Circumpolar Arctic. Over 300 profiles of total length of about 140,000 km and equations of correlation, which link the depth of the Moho discontinuity occurrence with Bouguer anomalies and the topography, were used for the map compilation. Correlation sketch map of crustal types, which differ in velocity and density parameters, structure, and total crust thickness, has been compiled based on the data of deep seismic studies on continents and in oceans. The sketch map of crustal types distribution, which was compiled based on seismic profiles in the Arctic, demonstrates the position of the oceanic and continental crust in the structures of the Circumpolar Arctic. Summary geotransect is composed of DSS seismic line fragments and supplemented with density modelling. The geotransect demonstrates structure of the Earth’s crust and upper mantle along the line 7600 km long, which crosses the continental crust of the East European Platform, Barents-Kara shelf seas, Eurasian Basin oceanic crust, reduced crust of the Central Arctic Submarine Elevations, shelf seas of Eurasia passive margin, and crust of the Chukotka-Kolyma folded area.

The chapter presents results of studying the seabed rocks from scarps of steep mountainsides of the Mendeleev Rise collected during the Arctic-2012 expedition. The seabed collection consists of five thousand samples dominated by sedimentary rocks of shallow shelf facies. Carbonates are dominated by massive dolomites and limestones, which contain Devonian to Permian fauna. Terrigenous rocks are mainly represented by quartz sandstone and siltstone. Judging by the composition and age, the sedimentary rocks of the Mendeleev Rise belonged to the platform cover of the Early Precambrian cratonic block, which forms the crystalline basement of the uplifts in the Central Arctic. Basalt and gabbro-dolerite occupy no more than 10–20% of the raised seabed rocks. The basalt of the Mendeleev Rise belongs to the intraplate moderately alkaline Permian-Triassic basalt of the trap formation of Siberia and the Jurassic-Cretaceous basalt of the High Arctic Province (HALIP).

The chapter provides results of the generalization and interpretation of deep geophysical studies. The model of the deep crustal structure is represented by a set of maps, showing the crustal thickness, and a 5400 km-long Geotransect, crossing major tectonic areas of northeastern Eurasia. A set of digital maps covering an area of 50,000,000 km2 is compiled in a single projection and includes the following maps: the Moho depth; the thickness of main crustal units (sedimentary cover and consolidated crust); the anomalous gravity field and anomalous magnetic field used for zoning of the area; crustal types. The Geotransect crosses North-Eastern Eurasia and characterizes the vertical section of the earth’s crust and upper mantle in the passive margin of the Eurasian continent (including submarine elevations of the Arctic Ocean and its shelf part), the active eastern continental margin and extends into the Pacific Plate.

Base on thorough interpretation of Russian seismic reflection data the sedimentary architecture of Amundsen and Nansen basins was studied. Accordingly, we infer four development stages of the Eurasian Basin (EB) sedimentary system, caused by tectonic evolution of the region.Continental break-up stage I ~120-56 MA leads to formation of 120-130 km wide synrift basins both in the Eastern Amundsen and in the Western Nansen basins. Both basins were floored by extremely extended continental crust. Therefore, the hypothesized continent-ocean boundary (COB) should be placed at the seaward edges of synrift portions of Amundsen and Nansen basins, roughly along the magnetic anomaly #20.Spreading stage II (56-34 MA) was characterized by seafloor spreading in the EB as low as 8 mm/year, which was accompanied by expansion of the Amundsen and Nansen sedimentary basins up to their current sizes. The successive expansion of the sedimentary basins which is characteristic of the seafloor spreading basin, was revealed from the architecture of only this sequence, neither underlying nor overlapping. We propose the formation of a Gakkel Ridge rift valley and its infilling with thick sediments sequence during this stage.Synoceanic stage III (34-~3 MA) was resulted in the accumulation of the undisturbed Oligocene-Quaternary sediment sequence all over the entire EB. If the non-tectonized architecture of this sequence indicates a calm tectonic regime for the most of the Oligocene-Miocene, the existence of the sediment veneer all over the entire EB proves that sedimentation basin and consequently the oceanic crust domain of modern size were already formed by the beginning of Oligocene.Re-spreading stage IV (~3-0 MA) is characterized by the resumption of seafloor spreading in the Gakkel Ridge axial zone by propagation of the oceanic rift from Norwegian-Greenland basin toward the east. The proposed model of two-stage seafloor spreading in the EB allows us to explain most of the geological issues in this region and is of perfect relation to the known tectonic events along the Arctic periphery.In particular: (1) thick sediments sequence in the Eastern and Central (e.g. at 94°E by Rekant & Gusev, 2016) Gakkel Ridge rift valley could be explained by the Eocene age of the rift valley, (2) recent spreading resumption could be considered as the cause of the unpredictable high both the hydrothermal activity and volcanism at the Western Gakkel Ridge, (3) the consolidated sand- and siltstones, dredged from the seamount scarp in the middle part of Amundsen Basin (Gaedicke et al., 2019), which thought to be fragments of Mesozoic continental crust, confirm the suggested COB position along magnetic anomaly No.20, (4) the eastward propagation of the ocean rifting along the Gakkel Ridge leads to apparent change of the accentuated high relief morphology of the Western Gakkel Ridge to a smoother ridge morphology of the Eastern Gakkel Ridge as well as to defocusing seismicity at the Eurasia Basin– Laptev Sea transition.

In 2019, the compilation of the new Tectonic Map of the Arctic (Tectonic Map of the Arctic, 2019: eds. O. Petrov, M. Pubellier) was completed. The map was compiled under the international project Atlas of Geological Maps of the Circumpolar Arctic, 1:5M with the participation of representatives of all Arctic states under the auspices of the Commission for the Geological Map of the World at UNESCO. The new 1:5M Tectonic map of the Arctic is a GIS project, which provides a transition to three-dimensional geological mapping of the Arctic. The project includes the crustal and sedimentary cover thickness maps, the crustal types map, the tectonic zonality map of the basement, schematic map of key igneous provinces of the Circum-Arctic region and the geological transect compiled taking into account the latest scientific geological and geophysical data accumulated in recent decades as a result of high-latitude expeditions and scientific programs to substantiate the extended continental shelf in the Arctic. The new Tectonic map of the Arctic proved the continental nature of the Central Arctic Uplifts as a natural geological extension of Eurasia. Close structural relationships of deep-water parts of the Central Arctic and the shallow continental shelf of Northern Eurasia are substantiated by geological and geophysical characteristics of the consolidated crust, the upper mantle and sedimentary cover, as well as the common parameters of the magnetic and gravitational potential fields.

Geological structure of western part of the Chukotka fold belt has been studied basing on the results of joint interpretation of geophysical data. The potential-field data, seismic and magnetotelluric data along two regional profile crossed the area and the off-shore seismic data obtained on the East Siberian sea were used in this study. The NE and NW oriented fault systems which control the mineragenous zones location were first detected and delineated. Joint interpretation of seismic and MT data along regional profiles allowed us to study: the deep structure of NW directed thrusts; the intrusion bodies morphology; the structural features of the Paleozoic and Mesozoic formations and the structure of volcanic deposits. The models of geological structure along regional profiles were used as a reference for potential field interpretation. Architecture of crystalline basement of the area was studied and several “steps” were detected. The depth of crystalline basement increases from north to south and reaches the largest depth under the volcanic deposits of Ochotsk-Chukotsk Volcanic Belt (OCVB).

The Circum-Arctic terrains comprise series of complex geological structures, with fragments of Archaean to Paleoproterozoic shields and platforms, remains of orogenic belts of Neo-proterozoic to Cenozoic ages, Paleozoic and Mesozoic platforms and sedimentary basins, large igneous provinces, and Mesozoic-Cenozoic rift structures and basin fill in the northern North Atlantic and Central Arctic Ocean. Major orogenic events include the Neoproterozoic Timian Orogeny, the Mid Paleozoic Caledonian and Eurekean orogenies, the Late Paleozoic to Early Mesozoic Ellesmerian and Uralian orogenies, and the Late Mesozoic to Cenozoic Eurekan orogeny. The breakup of Arctida-II in the Mesozoic and Cenozoic, and the Cenozoic sea-floor spreading in the North Atlantic and Polar Ocean, led to significant redistribution of land masses and to the formation of the present Arctic Ocean shelves and basins. The central Arctic Ocean remains one of the more debated areas in terms of plate tectonic evolution. Most models include spreading in the Canada Basin (southern Amerasia Basin) at ca. 125–80 Ma, the Makarov-Podvodnikov Basin (northern Amerasia Basin) at around 80–60 Ma, and the Eurasia Basin at ca. 55-0 Ma. Different crustal and tectonic models for the Amerasia and Eurasia basins and their margins are discussed, and present knowledge of the basin fill histories briefly reviewed. The present paper serves as an introduction to the current Special Issue on the Geodynamics of the Arctic.

Fossiliferous carbonate rocks dredged during the “Arctic-2012” cruise on the Mendeleev Rise (eastern Arctic) provide proof of the presence of Upper Silurian(?)–Middle Devonian, Famennian–Tournaisian, Bashkirian–Kasimovian, Gshelian–lower Asselian(?) and Kungurian–Kazanian carbonate deposits. The wide spectrum of facies includes deposits of both photic zone (with fusulinids, algae, relicts of microbial and coral reefs) and deeper dysphotic areas (with trilobites, deep-water tentaculitids and ostracods). The results obtained suggest that there were at least three periods of carbonate platform sedimentation during the latest Silurian(?) to Permian. The Late Silurian?–Devonian biota do not show biogeographical differentiation, but rather are distributed globally. Shallow-water foraminifera and some algae of early Pennsylvanian–basal Cisuralian age belong to the warm-water province. These forms are unknown in the Moscovian–Permian of the Boreal Realm (Taimyr, New Siberian Islands, Verkhoyanie, Omolon Massif) but are typical for Alaska and Arctic Canada, Wrangel Island, Chukotka, Polar Urals and Svalbard. The disappearance of warm-water biota during late Artinskian-Kungurian times led to a subsequent predominance of smaller foraminifera: this assemblage with Protonodosaria is widely distributed in Permian deposits of Novaya Zemlya, Urals, Barents Sea and the eastern Arctic. The warm-water Bashkirian-Asselian biota suggests that the Mendeleev-Chukotka-Wrangel block was a low-latitude shallow basin with predominant carbonate sedimentation, being part of the Arctida supercontinent, connected temporarily with the eastern margin of Laurasia (Chukcha-Alaska block).

The results of local U–Th–Pb-SIMS-SHRIMP-II analysis of the collection of pyrochlores from Nb rare-metal deposits of the Ilmeny–Vishnevogorsky alkaline complex are discussed. Independently of the chemical composition, the host rocks, and the stage of carbonatite formation, the studied pyrochlores are characterized by an almost undisturbed U–Pb isotope system. This allowed to estimate the age of ore mineralization on three deposits (Vishnevogorsky, Buldymsky, and Potaninsky) with an accuracy of ±1–6 m. y. The U–Pb system of the studied pyrochlore samples suggests three epochs of the mineral formation: 380, 230–240, and 216–218 Ma. Convergence of the results obtained by the different methods of U–Pb dating for one of the samples from our collection (±0.5–1.0 Ma) allows to use it as an in-house standard for local dating.

Deep seismic studies of the Sea of Okhotsk region started in late 1950s. Since that time, wide-angle reflection and refraction data on more than two dozen profiles were acquired. Only five of those profiles either crossed or entered the deep-water area of the South-Okhotsk Basin (also known as the Kuril Basin or the South-Okhotsk Deep-Water Trough). Only P-waves were used to develop velocity-interface models in all the early research. Thus, all seismic and geodynamic models of the Okhotsk region were based only on the information on compressional waves. Nevertheless, the use of Vp/Vs ratio in addition to P-wave velocity allows discriminating felsic and mafic crustal layers with similar Vp values. In 2007 the Russian seismic service company Sevmorgeo acquired multi-component data with ocean bottom seismometers (OBS) along the 1700-km-long north-south 2-DV-M Profile. Only P-wave information was used previously to develop models for the entire profile. In this study, a multi-wave processing, analysis, and interpretation of the OBS data are presented for the 550-km-long southern segment of this Profile that crosses the deep-water South-Okhotsk Basin. Within this segment 50 seismometers were deployed with nominal OBS station spacing of 10–12 km. Shot point spacing was 250 m. Not only primary P-waves and S-waves but also multiples and P-S, S-P converted waves were analyzed in this study to constrain velocity-interface models by means of travel time forward modeling. In offshore deep seismic studies, thick water layer hinders an estimation of velocities in the sedimentary cover and in the upper consolidated crust. Primarily, this is due to the fact that refracted waves propagating in low-velocity solid upper layers interfere with high-amplitude direct water wave. However, in multi-component measurements with ocean bottom seismometers, it is possible to use converted and multiple waves for velocity estimations in these layers. Consequently, one can obtain P- and S-waves velocity models of the sedimentary strata and the upper consolidated crust. Velocity values in the upper consolidated crust beneath the South-Okhotsk Basin (Vp = 5.50–5.80 km/s, Vp/Vs = 1.74–1.76) allow interpretation of this 2.5–3.5-km-thick layer to be consistent with a felsic (granodioritic) crust. These results suggest that the Earth's crust in this region can be considered continental in nature, rather than previously accepted oceanic crust. Even though, the crust is thinned and stretched at this location.

He, Ar, S, and Cu isotope characteristics of the Norilsk-1, Talnakh, and Kharaelakh ore-rich intrusions have been found to diverge. The intrusions’ isotope characteristics form regression lines with the Kharaelakh intrusion having the highest atmospheric contribution of Ar and the Norilsk-1—the least one: this correspond to a degree of interaction with the host-rock, believed to be a source of atmospheric Ar, though may relate to the intrusions occurrence depth. δ34S has been found to decrease at growth of m (3He/4He) with the highest proportion of mantle S and He revealed in the Norilsk-1 intrusion. δ34S versus δ65Cu demonstrates negative correlation suggesting probable Cu income from different sources rather than its isotope fractionation: in this instance the Kharaelakh ores are dominated by the crustal Cu, Ni isotopic compositions vary narrowly, displaying no pronounced correlation with He, Ar, S, and Cu isotopes, implying: (1) a single mantle source of Ni and its minute fractionation; (2) contamination of ore system and its fluids by S, Cu and noble gases from the host-rocks; (3) the revealed isotopic variations may be accounted for two or three sources of matter.

The influence of the size of conjugated π-system on catalytic activity of cobalt complex with β-octaphenylporphyrin and its tetraaza-, tetrabenzo and tetrabenzotetraaza derivatives was studied in present work. It is found that catalytic activity for oxidation of sulfur-containing compounds increases under extension of conjugated macrocycle system according to the following series CoP < CoBP ≤ CoPz < CoPPz ≪ CoPc.

We present a new model of the crustal and tectonic structure of the Arctic region north of 60° N latitude, constrained as a part of the international Atlas of Geological Maps of the Circumpolar Arctic under the aegis of the Commission for the Geological Map of the World. The region is largely formed by (i) Archean–Paleoproterozoic shields and platforms, (ii) orogenic belts of the Neoproterozoic to the Late Mesozoic ages overlain by platform and basin sediments, (iii) Cenozoic rift structures formed in part as a consequence of seafloor spreading in the North East Atlantic Ocean with propagation into the Central Arctic Ocean along the Gakkel Ridge, (iv) deep-water ocean basins and shallow-water shelves of the North Atlantic and Arctic Oceans, and (v) associated large igneous provinces (LIPs). We present a series of maps for the Circumpolar Arctic which include maps of the depth to Moho and thickness of the sedimentary cover and presents tectonic regionalization based on 18 major crustal types (oceanic, transitional, and continental) recognized in the Arctic. A 7600 km-long crustal geotransect across the region illustrates the details of its crustal and tectonic structure. We discuss geological, geophysical and geochemical datasets on which the new regional model is based. These include magnetic and gravity maps of the Circumpolar Arctic and a wide range of existing and recently acquired bathymetric, geophysical (including seismic), geological, isotope and geochronological data (illustrated by new age data for seabed and bedrock samples from the New Siberian Islands). The analysis of these data in the framework of regional tectonic evolution allows for correlating onshore and offshore lithospheric fragments and for recognizing regions with oceanic, transitional, and continental crust in the Circumpolar Arctic.

We present a seismic and density model for the crust and the uppermost mantle of the Arctic Ocean off-shore Chukotka down to a 40 km depth along a 740-km long latitudinal (at ca. 77°N) “Arctic-2012” wide-angle/MCS profile. Joint seismic and gravity modeling indicates significant differences in the crustal velocity and density structure of the northeastern Vilkitsky Trough, the Mendeleev Rise, the Chukchi Basin, and the Chukchi Plateau. The Vilkitsky Trough and the Chukchi Basin have a thin crust (23 km and 18 km, correspondingly), 6–8 km thick sedimentary cover, 3–6 km thick upper/middle crust (with the smallest thickness of 3–4 km beneath the Chukchi Basin), and 9–10 km thick lower crust. The uppermost mantle of the Chukchi Basin has a high density (3.27–3.31 g/cm3) and a low velocity (Vp ∼ 7.8 km/s), which we explain by 5–10% serpentinization of mantle peridotite at a 22–35 km depth as a result of crustal hyperextension and seawater penetration. The Chukchi Plateau and the Mendeleev Rise have a thick crust (28–29 km and 33–34 km, correspondingly), underlain by a normal mantle (Vp ∼ 8.0 km/s). The Chukchi Plateau has a 2‐4 km thick sedimentary cover, a thick (15–18 km) upper/middle crust with low-Vp, low-density lenses interpreted as magmatic intrusions, and a 9–12 km thick lower crust. The Mendeleev Rise has a 3–7 km thick sedimentary cover (most of which is formed by metasediments with a possible presence of volcanic rocks), a 7–8 km thick upper/middle crust, and a thick (20 km) lower crust which includes a 3–4 km thick high-velocity (Vp ∼ 7.3 km/s) underplated magmatic material. The high density anomaly (at depths >35 km) below the Mendeleev Rise is interpreted as an eclogitic body in the upper mantle lithosphere. Seismic Vp and Vp/Vs structure of the crust along the “Arctic-2012” profile indicates its continental nature: a 3–18 km thick upper/middle crustal layer with Vp ∼ 6.0–6.8 km/s and Vp/Vs ∼ 1.70–1.73 typical of felsic-intermediate continental upper crust is present along the entire profile. Strong variability of the crustal structure along the profile reflects its significant modification by metamorphism and magmatism, possibly related to the High-Arctic Large Igneous Province and localized lithosphere extension beneath the Chukchi Basin.

Mathematical kinematic model of a wheeled robot, operating according to the algorithm to achieve the specified coordinates was developed. Model was designed in visual programming platform LabView. The problem of control of autonomous mobile wheeled robot moving in two dimensions without obstacles was considered. Applicability of this model to the real problems of motor control and drive wheel robots was analyzed and future research directions was defined. The efficiency and effectiveness of the algorithm described was illustrated in the graphs of the mathematical model of the robot.

We present results of 40Ar/39Ar isotopic investigations concerning the dating of dolerites and basalts that were sampled during the Arctica-2012 polar expedition. Basalts were sampled by means of deep underwater drilling with wells up to 2 m in outcrops on the seafloor (basalts), and dolerite samples were obtained from the bottom of an escarp of Mendeleev Rise using a manipulator on the research submarine. The analysis results of the obtained mono-mineral fractions (amphibole, plagioclase, pyroxene) from the studied rocks yielded an Early Paleozoic age of the dolerites and basalts from Mendeleev Rise. The oldest ages obtained for amphibole reach 471.5 ± 18.1 and 466.9 ± 3.3 Ma, which corresponds to the Early-Middle Ordovician. The isotopic composition of argon was measured on two mass spectrometers: the Micromass Noble Gas 5400 (UK) and the Thermo Scientific Argus (Germany). The determined Early Paleozoic age of igneous rocks of Mendeleev Rise and seismic data obtained during the last Russian expedition Arctica-2012 [2] let us suppose that this continental block of the Earth’s crust has a Precambrian basement similar to the basement identified for the New Siberian islands including the De Long archipelago.

The New Siberian Islands terrane, represented on the Arctic shelf by the archipelagos of the New Siberian Islands and De Long Islands, is one of the key structures of the Arctic. However many questions of its structure, borders and formation history are under intense discussion. During the international expedition in 2011 we solved many problems concerning structural geology, paleontology, petrology and geochronology. A particular attention was given to obtaining paleomagnetic data for the sedimentary and igneous rocks of the archipelago. The primary objects of paleomagnetic studies were the Early Paleozoic sedimentary rocks of the Kotelny (Anzhu) and Bennett (De Long) islands. In this paper we present new paleontological data, includ� ing the first one for conodonts of the New Siberian Islands, which help us to specify the age of the Early Pale� ozoic deposits of the studied sections. In these sections we took a series of paleomagnetic samples. The match of the paleomagnetic directions we determined for Bennett Isl. and Kotelny Isl. indicates the tectonic unity between the territories of the Anzhu and De Long archipelagos. These first paleomagnetic data allow us to affirm that at least from the Early Ordovician the rocks of the Anzhu and De Long archipelagos formed within the same New Siberian Islands terrane, that is to say, on the same basement.

A thick (200 m) rock salt mass covering Late Archean granitoids was exposed for the first time in the Early Proterozoic volcanogenic-sedimentary formations in the Onega trough of the east Baltic Shield by the Onega parametric well. The mineral composition of salts, their geochemical features, and the isotopic composition of carbonate carbon and oxygen have been studied. After fluid inclusions present in salts, their metamorphism temperature and isotopic composition of helium and argon were determined. The obtained results give evidence of the fact that rock salts and magnesites associated with them were formed in an evaporate basin with participation of deep crustal processes. The age of the underlying granitoids (2.716 ± 9 Ma) is determined using the Pb—Pb method.

In this paper, we present a variable temperature (2)H solid-state NMR investigation of cryptophane-E:chloroform and cryptophane-E:dichloromethane inclusion complexes. The (2)H line shapes and nuclear spin relaxation rates were analyzed in terms of the distribution of C-D bond orientations and the time scale of the guest dynamics. It was found that encaged chloroform produces broad (2)H spectra, and that its reorientation is relatively slow with a correlation time of approximately 0.17 mus at 292 K. In contrast, the (2)H line shapes of encaged dichloromethane are narrow and the motion of this guest molecule is fast with a correlation time of approximately 1.4 ps at 283 K. The (2)H NMR data were complemented by an X-ray diffraction study of the cryptophane-E:dichloromethane structure, which was utilized in the analysis of the NMR parameters.

In this Letter, we demonstrate the use of separated local-field NMR spectroscopy under magic-angle spinning conditions as a means of studying molecular reorientation in solid inclusion compounds. S ...